1. Field of the Invention
This invention relates to a clip suitable for use in connecting two plates or the like together, and more particularly to a clip which includes a clip body comprising a leg projecting from the bottom surface of a flange and a pin whose shaft portion projects from the bottom surface of a head, and which can be used to fasten two plates together by forming a through hole in each one of the two plates, overlaying the plates with the two through holes aligned with respect to each other inserting the leg of the clip body into the through holes, and forcing the shaft of the pin into the leg so as to expand the tip of the leg of the clip body and thereby lockingly secure the clip within the two plates which in turn secures the two plates together.
2. Description of the Prior Art
In mounting a bumper on an automobile body, it is a common practice to fix the bumper fasciae to retainers on the body panels using synthetic resin clips.
One type of clip used for this purpose consists of a clip body comprising as a substantially cylindrical leg projecting from the bottom surface of a flange, and a pin whose shaft portion projects from the bottom surface of a head. This clip is used to fasten two plates together by forming a through hole in each one of the two plates to be fixed together, overlaying one plate on the other with the two through holes aligned, with respect to each other inserting the leg of the clip body into the through holes, and forcing the shaft of the pin into the leg so as to expand the tip of the leg of the clip body and thus clamp the two plates between the bottom surface of the flange of the clip body and the expanded tip of the leg.
A clip of this type is disclosed in Japanese Utility Model Public Disclosure Sho 55-120818 and is illustrated in FIGS. 12 and 13 of the drawings of the present patent application. As shown in these FIGURES, the clip has clip body 31 as comprising of a flange 33 with a central pin insertion hole and a substantially cylindrical leg 34 which is provided on the bottom surface of the flange 33 with its hollow interior in communication with the insertion hole and which is divided into four segments by four regularly spaced slits 35 formed in the wall of the leg 34 in parallel with the leg axis, and furthermore has a pin 32 comprising a shaft 37 extending from the bottom surface of a head 36 and four ribs 38 formed axially on the periphery of the shaft 37 in correspondence with the slits 35 of the clip body 31.
When the clip is used to fasten together two plates i and j formed with through holes k and l, the plates are overlaid with the through holes aligned with respect to each other and the leg 34 of the clip body 31 is inserted into the through holes as seen in FIG. 12. The shaft 37 of the pin 32 is then forced into the interior of the clip body 31. As shown in FIG. 13, the tip of the leg 34 has a small inner diameter and is pushed outward by the invasion of the shaft 37 so that the segments of the leg 34 flex outward, causing the mid-portion of the leg 34 to expand into pressure contact with the wall of the through hole l thereby clamping the plates i, j together between the expanded portion of the leg 34 and the flange 33. When the shaft 37 has been pushed all the way in, catch projections 40 formed on the inner walls of the segments of the leg 34 engage with a catch dent 39 formed on the shaft 37 of the pin 32, whereby the expanded state of the leg 34 is maintained, and the ribs 38 formed on the shaft 37 of the pin 32 come to rest in the slits 35 of the clip body 31.
However, this clip has insufficient strength against shearing forces. When a strong force acts on the plate i in the direction of the arrow F in FIG. 13, for example, the plates are liable to become unfastened owing to breakage of the clip. When clips of this type are used for mounting a heavy bumper on an automobile body, therefore, there is the danger of the bumper falling off owing to breakage of the clips. It is therefore desirable to increase the strength of such clips without incurring increased costs or other disadvantages.